In the United States, Cheddar cheese was traditionally produced in 18 kg (40 lb) blocks. In a highly cost-competitive market, more automated and efficient means of handling large quantities of cheese in rapidly expanding cheese factories were developed to control costs. Thus, in the late 1970s and early 1980s, the first 290 kg (640 lb) block Cheddar production lines were put into production. One 290 kg block replaced sixteen 18 kg blocks. The 290 kg block system reduced labor and handling costs, on-the-job lifting injuries, intermediate packaging costs, and trim loss when blocks were converted to the exact weight pieces needed for retail marketing.
However, although the handling of 290 kg blocks of cheese with forklifts was efficient and easy, the cooling of the cheese in these large blocks immediately after manufacture was more difficult. Thus, as the 290 kg block systems became common in the industry, it became apparent that the cheese within the 290 kg blocks had variations in both composition and cheese quality. For example, in 1988, Reinbold et al. (J. Dairy Sci. 71: 1499-1506) observed that after 7 days of cooling a 290 kg block of cheese, moisture had traveled from areas of high to low temperature. Reinbold et al. also observed that after 24 hours of cooling, the curd had not completely fused and was still porous.
Barbano et al. conducted systemic studies on 290 kg blocks of cheese and observed that a moisture gradient of about 5% existed from the inside to the outside of the cheese block. J. AOAC Intl. 84: 613-19 (2001). Thus the center of 290 kg blocks of cheese was significantly drier than the outside. Moisture was apparently wicking from the interior to the exterior during cooling of the cheese blocks, leading to irregularities and non-uniformities in cheese composition and quality. Smaller portions of cheese cut for retail sale from these 290 kg blocks were sometimes too wet, or too dry, depending upon what part of the block the retail portion was taken.
Hence, a problem exists in the cheese industry that threatens to undermine the efficient 290 kg block process routinely used for making cheese.